But you're always returning Monday, right? Your grouping will be
correct, but to get the actual truncation date, you have to subtract back.
select (date_trunc('week', '2007-03-07'::date + 5)::date-5);
select (date_trunc('week', '2007-03-06'::date + 5)::date-5);
select (date_trunc('week', '2007-03-08'::date + 5)::date-5);
Bruno Wolff III wrote:
On Fri, Mar 09, 2007 at 23:07:26 -0300,
Jorge Godoy <jgodoy@xxxxxxxxx> wrote:
But how to get the date if the first day of the week is a Wednesday? This
example is like the ones I've sent with separate queries that needed being
combined -- in a function, probably -- to get the desired result.
If you want to group on weeks that start on Wednesdays add 5.
postgres=# select date_trunc('week', '2007-03-07'::date + 5);
date_trunc
------------------------
2007-03-12 00:00:00-05
(1 row)
postgres=# select date_trunc('week', '2007-03-06'::date + 5);
date_trunc
------------------------
2007-03-05 00:00:00-06
(1 row)
postgres=# select date_trunc('week', '2007-03-08'::date + 5);
date_trunc
------------------------
2007-03-12 00:00:00-05
(1 row)
---------------------------(end of broadcast)---------------------------
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